Liquid-separating apparatus



Dec. 3, 1929. w. s. EDSALL LIQUID SEPARATING APPARATUS Filed Oct. 17,1922 2 Sheets-Sheet 1 Dec. 3, 1929. w. s. EDSALL 1,737,648

LIQUID SEPARATING APPARATUS Filed on. 17, 1922 2 Shuts-Sheet 2 PatentedDec. 3, 1929 UNITED STATES PATENT OFFICE WILLIAM S. EDSALL, OF READING,MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO CONDIT ELECTRICALMANUFACTURING CORPORATION, OF BOSTON, MASSACHUSETTS, A CORPORATION OFMASSACHUSETTS LIQUID-SEPARATING APPARATUS Application filed October 17,1922. Serial No. 595,173.

This invention relates to oil immersed electrical apparatus andparticularly to electric switches adapted to interrupt relatively largevalues of current.

During circuit interruption, a considerable amount of gas and vapor maybe generated in an oil immersed electric switch and, to relieve theinternal pressure that may otherwise be created by the gas and vapor,the switch casing may be vented and the vent may inelude a pipe ofsuitable dimensions which is in communication with the interior of theswitch before the oil level therein and may be extended to a suitableventing place. Usually the vent pipe terminates a short distance abovethe switch. Under severe circuit-interrupting conditions the evolutionof gas and vapor within the switch may be rapid and violent. and liquidoil may be and usually is forced with the vapor and gases through thevent pipe and discharged from the switch.

A discharge of oil from the switch is highly undesirable as. uponrepeated operations, the

oil level may descend to so low a point that the switch may be renderedineffective to interrupt its circuit safely. Furthermore, the oil andgas vapor are usually at an elevated temperature when expelled from theswitch and may even be on fire, or at such a high temperature as toignite spontaneously when discharged into the atmosphere, wherebyburning oil may be scattered about and may cause. disastrous fires.

An object of this invention is to provide a switch with venting meansincluding means to catch oil which may be expelled from the switchcasing, and return it to the switch casing; and cool the hot gases andvapors before passing them into the atmosphere; and condense condensiblevapors and return them to the switch.

A further object is generally to improve the construction and operationof electric switches.

Fig. 1 is a side elevation of an electric switch embodying theinvention.

Fig. 2 is a side elevation of the separator apparatus embodying theinvention.

Fig. 3 is a sectional elevation of the structure of Fig. 2.

Fig. 4 is a modification of the structure illustrated in Fig. 3.

Fig. 5 is a plan View of Fig. 2.

Fig. 6 is an elevation, partly in section, of a further modified form ofseparator apparatus.

Fig. 7 is a plan view of Fig. 6.

As here shown, my invention is or may be applied to an electricalapparatus, as an oil immersed electric switch which may be of anysuitable construction and may have the casing 10 adapted to contain oilor other suitable equivalent fluid. Said casing may contain the movableand stationary switch members; and the stationary switch members 11 mayextend upwardly above the casing for attachment with circuit leads. Theswitch may be enclosed in a cell or compartment having the top wall Aand the rear wall B.

The switch may be vented in any suitable manner as through the vent pipe12 which may be in communication with the interior of the switch casingand extend upwardly above the switch, and through the top wall A of thecell or to any suitable location at which gases and vapors formed withinthe switch may be discharged into the atmosphcre.

As previously stated, liquid oil may be and usually is carried alongwith the gas and vapor through said vent pipe and, in accord auce withthis invention, I provide means to separate oil from the gas stream andcatch the oil and prevent it from being discharged into the atmosphereand return the oil to the switch casing; and said means may also serveto cool the gas and vapor and condense the vapor and return thecondensate to the switch, whereby but cool gas may be finally dischargedinto the atmosphere.

Preferably said oil-separating and gas and vapor cooling means isincluded in the gas venting passage of the switch and niay be a part ofsaid vent pipe and preferably is attached to the upper end of said pipeand the gas and vapor and liquid oil are adapted to be discharged intosaid means.

Said oil separating and cooling means may comprise an apparatus whichmay include the co-acting upper and lower members or plates 15 and 16which may be and preferably are in the form of circular discs. Saidlower plate may have a passage 17 extended through it in the lowerportion of which the upper end of said vent pipe may be threaded; andsaid passage may comprise the gas entrance to the separating apparatus.Said lower plate may also be formed or provided with one, or preferablya plurality, of ribs or walls 18 which are spaced from each other andare preferably annular in form and concentric and extend upwardly fromthe upper face of said plate. The spaces between said walls are adaptedto form compartments 19 in which the 'oil is separated and collectedfrom the gas stream passing through the apparatus; and said walls are ormay be relatively high as compared to the distance between them, wherebyto form relatively narrow and deep compartments.

Said upper plate 16 is or may be formed in a similar manner and,accordingly, may be formed with the concentric and spaced annulardepending walls 20 which are adapted to enter the compartments 19 ofsaid lower plate 15 and depend for a substantial distance therein and bespaced from the upstanding walls 18 of said lower plate. Said upperplate may be spaced above the tops of said walls 18 as illustrated inFig. 4, for instance, whereby to provide a gas passage from the middlepassage 17 of said lower plate over the edges of said walls 18 and 20into and out of the compartments 19, or said plate may rest upon thewalls 18 of said lower plate, as illustrated in Fig. 3 and, in suchposition, the passage through the separator apparatus is normally closedalthough the closure may not be absolutely gas tight, and the switch maybreathe. The cooled gas, from which liquid oil has been separated, isadapted to leave the separator apparatus in a downward direction throughthe annular assage 22 formed between the outermost wa s 18 and 20 of thelower and upper plates.

Said plates are held in spaced relation by suitable means which mayinclude the studs 25 which may be threaded in or otherwise secured tothe lower plate 15 preferably beyond the outermost wall thereof andextended upwardly. Said upper plate 16 is preferably slidably receivedon said studs and, in its lowermost position, is adapted to engage thewalls 18 of said lower plate, Fig. 3, or shoulders on said studs, Fig.4. Compression sprin s 26 may be disposed on said studs and are adaptedto bear against said upper'plate 16 and nuts 27 which are threaded onthe upper ends of said studs. This arrangement is such that normally theupper plate 16 is held yieldingly in its lowermost position withrelation to said lower plate and may move upwardly against said springsupon the occurrence of a predetermined increase in pressure between saidplates, whereby to increase the area of the gas passage through theapparatus and relieve, to some substantial degree, the gas pressure inthe apparatus, and also to reduce the strain on the plates and studs.Preferably, however, the extent of upward movement is not so great as towithdraw the annular walls 20 of said upper plate from an effectiveposition within the compartments 19 of said lower plate.

When the circuit including the switch isinterrupted under heavy load,gas and vapor are generated due to the action of the are upon the oil orother arc-quenching fluid, and the gas and vapor, and also liquid oilare expelled from the switch into the vent pipe 12. The gas stream andthe oil pass into the passage 17 in said lower plate and impinge againstthe upper plate 16 and are deflected laterally and pass into anddownwardly through the annular space between the first annular walls 20and 18 and into the first conipartment 19 of said lower plate. The gasstream thence whips abruptly about the lower edge of said annular wall20 and passes upwardly along said wall and into the next compartment andso on until it leaves the separator apparatus through the final ventpassage 22. The gas stream is adapted to pass at a relatively rapid ratethrough the apparatus and as it passes over the lower edge of each wall20 its direction of motion is changed abruptly. The oil contained in thegas stream is relatively heavy, as compared to the density of the gasand, consequently, as the gas stream is deflected over the edges of saidwalls 20, the oil particles are projected downwardly beyond and out ofthe gas stream and fall into the bottoms of the compartments. Saidcompartments are adapted to be relatively deep and the lower portionsthereof are adapted to form dead gas spaces in which the oil is retainedand prevented from re-entering the gas stream.

Oil may be separated from the gas stream in each compartment and the gasstream may fin lly flow from the separator apparatus substantially freefrom oil.

The entrapped oil in said compartments may subsequently flow back intothe switch through the passages 30 which extend from the bottoms of saidcompartments into a passage 31, which latter is or may be arranged incommunication with the middle passage 17 in said lower plate. Ifdesired, however, each compartment may be provided with separatedraining passages, although not herein shown. Said passages 30 and 31are adapted to be relatively small in crosssection, as compared with themain gas passage through the apparatus, whereby to prevent the separatcdoil from being blown back into the gas stream passing through the upperportion of said compartments.

The oil will be returned to the switch through the Vent pipe 12immediately subsequent circuit-interruption.

Due to the relatively small spacing between the walls 18 and 20 of saidupper and lower plates, the hot gas and vapor may come in intimatecontact with said cold walls and become cooled and vapor may becondensed and the gas may be relatively cool when it finally passes intothe atmosphere.

It is to be noted that the area between the walls of the upper and lowerplates is increased from the center toward the periphery of the platesand the gasconsequently expands as it passes through the apparatus, andthe expansion of the gas aids in the cooling of the gas and thecondensing of the oil vapor.

Fig. 6 illustrates a modified form of separator apparatus. In thismodification the lower plate 15 is'or may be identical with the plate15. The upper plate 16 may be similar to'the upper plate 16 and have thedepending annular walls 20 which are adapted to enter the compartments19 of said lower plate. The said 11 per plate may be formed with .theupstan ing peripheral flange 40 on top of which a cover plate 41 is ormay be secured by suitable means, as the screws'42, whereby to form aclosedupper compartment 43. Said plate 16 is or may be formed with a hub44 which extends into said compartment 43 and may terminate a suitabledistance below the cover plate 41. Said hub is provided with a passage45 which preferably is disposed above and may be substantially equal incross-section to the passage 17 in-said lower plate 15. Said cover platemay be formed with the projecting portion 46 which depends into saidpassage 45 and serves as a guide-member adapted to direct oil from saidpassage into said compartment 43.

The gas and oil insaid pipe 12 may be movingat considerable velocity atthe moment ofentering the separator apparatus and the oil partclesconsequently may have considerable momentum. Due .to the momentum, theoil particles may be projected upward from the gas stream as said streamis deflected laterally to pass outwardly between said plates 15 and 16*,The projected oil particles may enter said passage 45 at considerablevelocity and may be guided by -saidcover plate 41 to enter the closedcompartment 43 wherein the oil may 'be entrapped. With this arrangement,the-larger proportion of oil may be separated from the gas stream beforeit enters said compartments 19 and much of the remaining oil, andespecially the more finely divided particles may be separated from thegas stream in said compartments 19; Oil may return to the oil receptaclefrom said closed compartment 43 through the drain passage 50 subsequem:to the circuit interruption. v

The structure may be otherwise modified without departing from thespirit of the invention.

I claim:

1. Separating apparatus including a casing having a plurality of liquidseparating, open-top compartments, and means to guide aliquid-containing gas stream in succession through said compartmentsincluding a cover spaced above said compartments having flangesdepending into the uppermost portions only and spaced from the sidewalls of said compartments, and yielding means responsive to pressureconditions in said casing for'normally holding said cover in theaforesaid relation.

2. Separating apparatus including a casing having a gas inlet passageand an annular open-top compartment surrounding and in communication atits top with said passage, a cover spaced above said passage andcompart-ment and having a flange de ending into the uppermost portionsonly an spaced from the side walls of said com artment, and yieldingmeans responsive to pressure conditions in said casing for normallyholding said cover in the aforesaid relation.

3. Separating apparatus including a casing having a gas inlet passageand a plurality of annular, open-top compartments surrounding saidpassage, and means to guide a liquid containing gas stream from saidpassage in successionthrough said compartments including a cover spacedabove said passage and compartments and having flanges depending intothe uppermost portions only of and spaced from the side walls of saidcompartments, said compartments having channels in communication withthe lower portions thercof and with said gas inlet passage. I

4.-Separating apparatus including a casing having a gas inlet passageand a plurality of annular, open-top compartments surrounding saidpassage, and means to guide a liquid-containing gas stream from saidpassage in succession through said compartments including a cover spacedabove said passage and compartments and having flanges depending intoandspaced from the side walls of said compartments, said compartmentshaving channels in communication with the lower portions thereof andwith said gas inlet passage, and yielding means holding said cover inthe aforesaid relation.

a plurality of annular compartments arranged in series, and means toguide a gas vstream successively between and over the tops lOl 5. Aliquid separator apparatus including a being out of the gas stream, andmeans including said gas venting passage to conduct the separated liquidout of said compartments.

6. Separating apparatus including a casing having a plurality ofliquid-separating, open-top compartments and means to guide aliquid-containing gas stream in succession through said compartmentsincluding a loose cover for said compartments having flanges dependinginto the uppermost portions only and spaced from the side walls of saidcompartments, thereby to provide dead-gas pockets beneath saidcover-flanges, studs carried by and extended above said casingexternally of said compartments and extended loosely through said cover,and springs encircling said studs above said cover and bearing upon saidstuds and cover, Whereby to hold said cover yieldingly in the aforesaidrelation.

7. Separating apparatus including a casing having a gas inlet passageand a plurality of annular open-top compartments surrounding saidpassage, and means to guide a liquid-containing gas stream from saidpassage in succession through said compartments includinga cover spacedabove said passage over said compartments and having flanges dependinginto the upper portions only and spaced from the side and bottom Wallsof said compartments, and yielding means normally holding said cover inthe aforesaid relation arranged to permit said cover to be raised by andupon occurrence of an abnormal pressure within said casing.

8. Separating apparatus comprising a pair of opposed and spaced platesprovided with intermeshing annular ribs spaced apart to provide a gaspassage therebetween and thereover, said passage being freely open tothe atmosphere at the peripheries of said plates, one of said plateshaving an inlet in the middle of said plate adapted to communicate withsaid gas passage, and yielding means responsive to pressure conditionsin said passage securing said plates in the aforesaid relation.

9. Separating apparatus including a casing having a gas inlet passageand plurality of annular, open-top compartments surrounding saidpassage, and means to guide a liquid-containing gas stream from saidpassage in succession through said compartments including a cover spacedabove said pazsage and compartments and having flanges depending intothe upper portions only of and spaced from the side and bottom walls ofsaid compartments, and studs carried by and extended above said casingexternally of said compartments, said cover having a sliding support onsaid studs and arranged to yield and slide thereon upon '00- currence ofan elevated pressure in said casing.

10. Separator'apparatus having a gas entrance, a closed compartmenthaving an entrance opposite said gas entrance, and a gas exit passagearranged in front of said closed compartment and at an angle with thegas entrance.

11. Separator apparatus having a gas entrance, a closed compartmenthaving an entrance opposite said gas entrance, and a gas exit passagearranged in front of said closed compartment and at an angle with thegas entrance and a plurality of oil separating compartments arranged inseries in said exit passage.

12. The combination of a casing adapted to contain oil and having meansto provide a gas venting passage, and separator apparatus having a gasentrance arranged in communication with said gas venting passage and anoil-catching compartment having an entrance disposed above and oppositesaid gas entrance, said separator apparatus also having a gas exitpassage extended laterally between said gas entrance and said compart'ment-entrance and oil-separating compartments arranged in said gas exitpassage.

13. Separator apparatus comprising a casing having a gas inlet passageand a plurality of annular open-top, liquid-separating compartmentssurrounding said passage, and means to guide a liquid-containing gasstream to pass in succession from said inlet passage through saidannular compartments including a cover located above said passage andcompartments and having a plurality of annular flanges depending intoand spaced from theside and bottom walls of said compart ments, saidcover having a closed compartment located above said separatingcompartments and having an entrance opposite said gas inlet passage.

14. Separator apparatus'comprising a casing having a gas inlet passageand a plurality of annular open-top, liquid-separating compartmentssurrounding said passage, and means to guide a liquid-containing gasstream to pass in succession from said inlet passage through saidannular compartments including a cover located above said annularcompartments and having a plurality of annular flanges depending intoand spaced from the side and bottom walls of said compartments, saidcover having a closed compartment located above said separatingcompartments and having an entrance opposite said gas inlet passage, andpressure-responsive yielding means to hold said cover in the aforesaidrelation.

In testimony whereof, I have signed my 1 CERTIFICATE OF CORRECTION.

Patent No. 1,737,648. Granted December 3, 1929, to

WILLIAM S. EDSALL.

it is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1.line 13, for the word "before" read "above"; page 3, line 43, before theword "pipe" insert the word "vent", and line 46, for the misspelled word"partcles" read "particles"; page 4, line 114, claim 14, for the word"annular" read "passage and"; and that the said Letters Patent should beread with these corrections therein that the same may conform to therecord of the case in the Patent Office.

Signed and sealed this 21st day of January, A. D. 1930.

M. J. Moore, (Seal) Acting Commissioner of Patents.

